/*
 * Copyright 2009 Tran Nhut Trung.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); 
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, 
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and 
 * limitations under the License.
 */
package org.eclipse.core.databinding.observable.gwt.internal;

import com.google.gwt.user.client.ui.HasHTML;
import com.google.gwt.user.client.ui.Widget;

import org.eclipse.core.databinding.observable.Realm;
import org.eclipse.core.databinding.observable.gwt.IWidgetObservable;


public class HasHTMLObservableValue extends WidgetPropertyObservableValue implements IWidgetObservable {
  private HasHTML htmlWidget;

  public HasHTMLObservableValue(HasHTML htmlWidget) {
    this(Realm.getDefault(), htmlWidget);
  }
  public HasHTMLObservableValue(Realm realm, HasHTML htmlWidget) {
    super(realm, (Widget)htmlWidget, "HTML");
    this.htmlWidget = htmlWidget;
    
    this.oldValue = doGetValue();
  }

  protected void doSetApprovedValue(Object value) {
    if (htmlWidget == null){
      return;
    }

    try {
      updating = true;
      htmlWidget.setHTML(value==null? "" : (String)value);
      oldValue = doGetValue();
    } finally {
      updating = false;
    }
  }

  public Object doGetValue() {
    if (htmlWidget == null){
      return null;
    }
    
    return htmlWidget.getHTML();
  }

  public Object getValueType() {
    return String.class;
  }
}
